Process for the dyeing of aromatic polyamide fibres

ABSTRACT

PROCESS FOR THE DYEING OF AROMATIC POLYAMIDE FIBRES, PARTICULARLY AROMATIC POLYAMIDE FIBRES HAVING A HIGHLY CRYSTALLINE PHYSICAL STRUCTURE WHEREIN SAID FIBRES ARE DYED WITH AN AQUEOUS DYE LIQUOR CONTAINING A CATIONIC OR DISPERSE DYE AND AT LEAST ONE COMPOUND HAVING THE FORMULA R-O-(CH2-CH(-Z)-O)N-H WHEREIN R IS PHENYL OR A CHLORO-SUBSTITUTED PHENYL GROUP, Z IS HYDROGEN OR METHYL AND N IS AN INTEGER FROM 1 TO 3, AND EACH Z BEING, INDEPENDENTLY FROM EACH OTHER, HYDROGEN OR METHYL WHEN N IS 2 OR 3, OBTAINING ON SAID FIBRES AN EXCELLENT COLOUR YIELD.

United States Patent US. Cl. 8-173 12 Claims ABSTRACT OF THE DISCLOSUREProcess for the dyeing of aromatic polyamide fibres, particularlyaromatic polyamide fibres having a highly crystalline physical structurewherein said fibres are dyed with an aqueous dye liquor containing acationic or disperse dye and at least one compound having the formulawherein R is phenyl or a chloro-substituted phenyl group, Z is hydrogenor methyl and n is an integer from 1 to 3, and each Z being,independently from each other, hydrogen or methyl when n is 2 or 3,obtaining on said fibres an excellent colour yield.

DESCRIPTION OF THE INVENTION The present invention relates to a processfor the dyeing of aromatic polyamide fibres.

It is well known that conventional methods of dyeing certain syntheticpolyamide fibres having a highly crystalline physical structure are notsatisfactory. We have found, surprisingly, that when the dyeing of suchfibres is carried out in the presence of certain phenoxyethanolderivatives, extremely good results are obtained.

According to the present invention there is provided a process for thedyeing or printing of aromatic polyamide fibres having a highlycrystalline physical structure comprising treating said fibres with anaqueous dye liquor containing a cationic or disperse dye and at leastone compound having the Formula I wherein R is a phenyl orchloro-substituted phenyl group, Z is hydrogen or a methyl group and nis an integer from 1 to 3, and each Z being, independently from eachother, hydrogen or methyl when n is 2 or 3.

The compound of Formula I may be envisaged as the condensation productof a phenolic derivative with ethylene oxide or propylene oxide or withmixed ethylene oxide and propylene oxide.

A preferred fibre is one derived from an aromatic polyamide ashereinafter defined. Such an aromatic polyamide is one having aninherent viscosity measured in concentrated sulphuric acid at 30 C. ofat least 0.6, and a melting point of at least 300 C. which polyamidesare made up of the structural unit:

H H O O -I IAr I I C J-Ar2( wherein Ar; and Ar are the same or differentand are substituted or unsubstituted divalent aromatic radical in whichthe chain extending bonds are not ortho oriented with respect to eachother or to bonds linking one aromatic ring directly or through alinking group to another aromatic ring, the substituent groups (if any)in the aromatic rings being groups which do not react with amino orhalide groups during polymerisation and the total number of carbon atomsin substituent groups attached to any one aromatic ring not exceedingnine, subsject to the proviso that at most 10 mol percent of the Arradicals and at most 10 mol percent of the Ar radicals may be replacedby nonarornatic radicals. The polyamide is preferably Wholly aromatic";that is to say, none of 'the Ar fiadicfals or Ar radicals are replacedby nonaromatic ra- 1ca s.

The invention is particularly applicable to polyamides having aninherent viscosity, measured as described above, of at least 0.8. Onesuch polyamide is poly (meta-phenylene isophthalamide), and an exampleof a commercial fibre of an aromatic polyamide. fibre on which themethod of the present invention gives particularly advantageous resultsis that sold under the Trademark Nomex such as Nomex Type 430 or 450.Such fiber is a poly (metaphenylene isophthalamide) Cationic dyes whichmay be used in the process of the present invention may contain oniumgroupings such as ammonium, sulphonium or .phosphonium groups.

For instance, the usual salts of cationic dyestuffs, e.g. the halides,sulphates, alkyl sulphates, aryl sulphonates or metal halide doublesalts such as zinc chloride double salts, of a wide variety of cationicdyestufis may be used. In particular cycloammonium salts of methine,azamethine, triazene or especially of monoazo dyestuifs may be used.Alternatively, cationic dyestuffs of the diphenylmethane,triphenylmethane, oxazine or thiazine series may also be used accordingto the present invention. As a further possibility, salts of cationicdyestuifs of the arylazo or anthraquinone series having an externalonium group, for example an alkylammonium or cycloammonium group and thebenzo-l, 2 pyrane dye salts containing cyclammonium groups may be used.

Particularly suitable in the colouring process according to theinvention is the use of cycloammonium azo dye salts corresponding toFormula II The symbols in this formula have the following meanings:

A represents the radical of an optionally benzocondensed N-quaternatedazole or azine ring, preferably a thiazolium, benzthiazolium,imidazolium, benz'imidazolium, pyridinium, quinolinium, pyrazolinium,indazolium triazolium or thiadiazolinium radical.

B represents the radial of a coupling component free of hydroxyl groupsin the nucleus and enolisable keto groups, especially a p-aminophenylradical or -naphthyl radical, a 3-indazolyl, 3-indolyl,2,4,6-triamino-5-pyrimidyl or 5- amino-4-pyrazolyl radical, and

X represents the anionic acid equivalent.

Disperse dyes which may be used include for instance, an azo,anthraquinone, nitro, methine, styrene, azostyrene, nitroacridone,coumarine, naphthoperinone, quinophthalone or naphthoquinone iminedyestuff.

The amount of dye that is used may vary depending upon the circumstancesand may be an amount up to 10% by weight based on the weight of fibre.Cationic dyes are preferred.

The dyeing process according to the invention is preferably carried outusing a compound of Formula I wherein R and n are as previously definedand Z is hydrogen.

Suitable compounds having the Formula I which may be used in the processof the present invention are, for instance, phenoxyethanol, compoundsderived from condensation of one or three moles of ethylene oxide or onemole of propylene oxide with one mole of monochlorophenol, such aso-chlorophenol, m-chlorophenol or p-chlorophenol or with any mixture ofisomeric monochlorophenols, and compounds derived from condensation ofone mole of ethyleneoxide or propylene oxide with one mole ofdichlorophenol or trichlorophenol.

Especially satisfactory results of broad applicability to a greatvariety of dyestuffs are obtained with these compounds of Formula Iwhich are condensation products of one mole of ethylene oxide and onemole of a mixture of ortho-chlorophenol and para-chlorophenol in aweight ratio of from 1:4 to 1:6, specifically that mixture containing20% by weight of o-chlorophenol and 80% by weight of p-chlorophenol.

In certain circumstances, it is desirable to combine the compound ofFormula I with a water-soluble alcohol or a ketone having at most carbonatoms which is miscible with the compound of Formula I, for example,methylated spirits, isopropyl alcohol, ethylene glycol, methyl ethylketone or monoethers of ethylene glycol, such as ethylene glycolmonomethyl ether or ethylene glycol mono butyl ether.

The compounds having the Formula I may also be used, if desired, inadmixture with an organic solvent described in British patentspecification No. 856,381, which is liquid under the conditions of thedyeing of the present invention. A particularly preferred solvent ofthis type is benzyl alcohol. Particularly advantageous results areobtained in dyeing when the proportion of benzyl alcohol is within therange of from 20% to 50%, and especially from 20% to 30%, by volumebased on the total volume of the mixture benzyl alcohol and compound ofFormula I.

The amount of the compound having the Formula I or the mixture thereofwith an organic solvent as hereinbefore defined, especially benzylalcohol, used in the process of the present invention may be within therange of from 0.25% to 5%, and preferably from 1% to 3% by volume, basedon the total volume of the dye liquor.

The process according to the present invention may conveniently becarried out batchwise; or, if desired, the process may be carried outcontinuously, for instance by padding or printing followed by steaming.The temperature at which the dye is applied will normally be at least100 C. and not higher than 140 C.; a preferred range of temperature isfrom 120 to 135 C.

Where the process is carried out batchwise, the compound having theFormula I may be added directly to the dyebath and the polyamide fibremay be immersed in the aqueous dye liquor thus formed. The duration ofthe dyeing will depend on the circumstances, but generally a period offrom 30 minutes to 3 hours will suflice. From 5% to 30% by weight offibre based on the weight of aqueous dye liquor will normally be dyed insuch a dyebath, and for optimum results We restrict to from to 25% byweight.

There may alsobe present, if desired, in the aqueous dye liquor,inorganic or organic acids and/ or the watersoluble salts thereof toadjust the pH of the dyebath in order to achieve exhaustion onto thefibre. Suitable acids or salts are for example sulphuric acid,phosphoric acid, ammonium acetate, ammonium sulphate, alkyl or arylsulphonic acid, formic acid, lactic acid, chloracetic acid andparticularly acetic. acid. They are preferably used in amounts from0.25% to 5% by weight based on the total weight of fibre to be dyed.

The presence of neutral salts that are conventionally used in dyeingprocesses is particularly advantageous in the process of the presentinvention, for example sodium sulphate or sodium chloride. The amount ofneutral salt used is preferably in the range of from 10% to 30% byweight based on the weight of fibre to be dyed.

If desired a surface active agent may be present which is preferablycationic or non-ionic.

Where a printing or padding process is used, an optionally thickenedliquor containing dye, acid or acid salt and the compound of Formula Iis printed or padded onto the fibre, preferably at a temperature between10 C. and 40 C. The padded or printed fibre material may then 4 besteamed, preferably with steam at superatmospheric pressure for a periodfrom 10 to 30 minutes.

The process of the present invention gives an outstanding colour yieldon the materials which are dyed, the colour yield being superior to thatobtained when a conventional assistant such as benzyl alcohol alone isused.

The following examples further illustrate the present invention. Inthese examples parts and percentages are expressed by weight unlessotherwise stated. Parts by weight shown therein bear the same relationto parts by volume as do kilograms to litres. The temperatures are givenin degrees centigrade.

EXAMPLE 1 4 parts of Nomex aromatic polyamide yarn were immersed in 40parts by volume of an aqueous solution containing:

(a) 0.1 part of a dyestufi having the formula:

(b) 0.08 part of 40% aqueous acetic acid Comparative Example A Byfollowing a similar procedure to that described in Example 1, butomitting component (c) from the dyebath a poor depth of shade wasobtained.

Comparative Example B By following a similar procedure to that describedin Example 1, but using 4 parts of benzyl alcohol instead of 0.8 partscomponent (0) there used, only a moderate depth of shade was obtained.

EXAMPLE 2 The procedure described in Example 1 was repeated with theaddition of 0.8 part of sodium chloride to the bath; an even greatercolour yield Was obtained than that obtained in Example 1.

EXAMPLE 3 The procedure described in Example 2 was repeated usinghowever 0.2 part of dye instead of the 0.1 part there used; an excellentcolour yield was obtained.

EXAMPLE 4 The procedure described in Example 1 was repeated usinghowever a dyestuff having the formula instead of the dye there used; anexcellent colouryield was obtained.

EXAMPLE 5 The procedure described in Example 2 was repeated usinghowever the dyestufi having the formula given in Example 4 instead ofthe dye there used; an excellent colour yield was obtained.

5 EXAMPLE 6 The procedure described in Example 3 was repeated usinghowever a dyestutf having the formula;

chlorophenol and 80% p-chlorophenol instead of component (c); anexcellent colour yield resulted.

EXAMPLE 8 s H300 m 5 The procedure described 1n Example 1 was repeated cusing however 0.8 part by volume of a compound derived from 3 moles ofethylene oxide per mole of a mixczmOH ture comprising 20% o-chlorophenoland 80% p-chloroh 1' t d l mstead of the dye there used; an excellentcolour y1e1d g ifiz f ea of component (c) an excel em colour yleld wasobtamed' EXAMPLE 7 If in the above examples the dye salt components arereplaced by corresponding amounts of the salt of cationic The proceduredescribed in Example 1 was repeated dye-stuflfs which are listed in thefollowing table, column using however 0.8 part by volume of a mixturecontain- 2, the procedure being otherwise as in the Examples 1 ing 40%,2,4-dichlorophenoxyethanol and 60% of a comt0 8, then likewise areobtained dyeings of the shades pound derived from the condensation of 1mole of ethylgiven in the last column of that table, which have similarene oxide with 1 mole of a mixture comprising osatisfactory properties.

TABLE Shade on aromatic poly- Example No Salt of cationic dyestuflsamide fibres 9 FL'S 63 Red.

N=N-- f) 6 CH: HaC

10... "HaC-F-EIJH /CH2 6) Red.

N CH 6 CHaSO4 11 CH: Q

H J- (FH! or H c N=N N \s Q Q 12 sCfi-fi/' /C a Q Scarlet. H:CN\C-N=N-N\ CH 0009 N/ Q r Hz 13.-.- T-N H| 63 Orange.

k N: -NH 01 14 (1H1 ea Violet CH 3 CN=NN I Nasot CH3 i CH:

I on,

N: Q 111F04 N CH3 CH:

16 Q Q Orange.

. NH- I C-N=N -NHC2H5 Ol III NH-Oflu CH:

TABLE-Continued Shade on aromatic poly- Example No. Salt of cationicdyestufis amide fibres 35 "CHsl(i EH 6) Yellow.

CHa- N=N- solona 30.--:.:.:..:r.:. S 09 D:

-N No N I Q a 1 \N CH3 41H:

7 "25.15:. S Q ,DO. 3 H300 N=N-N-NO2 ZnCl; Ha

38.--:.:.:.:.:-:. 9 0 Blue;

H @j a CHaSOa Cl 0 i H5C2 02115 4 Green:

41 Violet.

(CHshN N( a)z I N( a)2 EXAMPLE 42 (a) 0.2 parts of a dyestutt having theformula The procedure described in Example 1 was repeated, using howeverthe product derived from condensation of 1 mole of propylene oxide with1 mole of a mixture of 20% o-chlorophenol and 80% p-chlorophenol insteadof component (c); an excellent colour yield resulted.

EXAMPLE 43 (c) 5.0 parts by volume phenoxyethanol (d) 0.8 parts sodiumchloride The dyeing was carried out at a temperature of 130 C.

The procedure described in Example 1 was repeated, using however theproduct formed by condensing 2 moles for 2 on complemnpf the dyemgPeriod i yam of ethylene oxide and 1 mole of propylene oxide with was mscoured and dned good colour yleld was a mixture of 20% o-chlorophenoland 80% p-chloroobtained phenol, instead of component (c); an excellentcolour EXAMPLE 45 Yleld resulted. Q 4 parts Nomex aromatic polyamideyarn were im- EXAMPLE 44 mersedin 40 parts by volume of an aqueoussolution 4 parts Nomex aromatic polyamide yarn were imai i mersed in 40parts by volume of an aqueous solution (a) 0.2 parts of the dyestulfhaving the formula given in contaimng: Example 44 13 (b) 0.08 part of40% aqueous acetic acid 2.0 parts by volume of a mixture (50/50) ofph'enoxyethanol and benzyl alcohol (d) 0.8 part sodium chloride.

4 parts Nomex aromatic polyamide yarn were immersed in 40 parts byvolume of an aqueous solution containing:

(a) 0.16 part of the dyestulf having the formula (b) 0.08 parts of 40%aqueous acetic acid (0) 5.0 parts by volume phenoxyethanol (d) 0.8 partssodium chloride The dyeing was carried out for 2 hours at 130 C. Oncompletion of the dyeing period the yarn was rinsed, scoured and dried.A moderate colour yield was obtained.

EXAMPLE 47 4 parts Nomex aromatic polyamide yarn were immersed in 40parts by volume of an aqueous solution containing:

(a) 0.16 parts of the dyestuff having the formula given in Example 47(b) 0.08 part of 40% aqueous acetic acid (c) 2.0 parts by volumemonochlorphenoxyethanol (d) 0.8 part sodium chloride.

The dyeing was carried out for 2 hours at 130 C. On completion of thedyeing period the yarn was rinsed, scoured and dried. A moderate colouryield was obtained.

EXAMPLE 48 A length of Nomex aromatic polyamide fabric was passedthrough a padding liquor containing:

(a) 2 parts of the dyestutf having the formula given in Example 44 (b) 3parts of 80% aqueous acetic acid (c) 1.6 parts of a locust bean gumderivative as thickener (d) 2 parts by weight of monochlorphenoxyethanol(e) water to make up to 100 parts.

14 EXAMPLE 49' Nomex aromatic polyamide yarn was passed through a yarnprinting machine and was then impregnated with a solution containing:

(a) 2 parts of the dyestuff having the formula given in Example 6 (b) 3parts of aqueous acetic acid (c) 1.6 parts of a locust bean gumderivative as thickener (d) 2 parts by weight of monochlorphenoxyethanol(e) water to make up to parts.

The impregnated yarn was steamed for 10 minutes at a temperature of C.After steaming the material was rinsed well in cold water and dried.

The yarn was dyed to a medium blue shade. By comparison Nomex yarnprinted with a solution formulated as above but without component (d)and otherwise similarly treated was dyed to a blue shade much paler thanthat obtained in the example.

We claim:

1. A process for the dyeing of a fiber comprising poly(meta-phenyleneisophthalamide) having a highly crystalline physicalstructure comprising treating said fibres with a cationic or dispersedye in an aqueous medium consisting essentially of at least one compoundhaving the Formula I wherein:

R is phenyl or chlorophenyl,

Z is hydrogen or methyl,

n is 1, 2 or 3, and each Z being, independently from each other,hydrogen or methyl when n is 2 or 3, at a temperature of from 100 to 140C.

2. A process as claimed in claim 1 wherein Z is hydrogen.

3. A process as claimed in claim 2 wherein R is phenyl, Z is hydrogenand n is 1..

4. A process as claimed in claim 2 wherein R is monochlorophenyl, Z ishydrogen and n is 1.

5. A process as claimed in claim 4 wherein the compound of Formula I isderived from condensation of 1 mole of ethylene oxide with 1 mole of amixture containing 20% by weight of o-chlorophenol and 80% by weight ofp-chlorophenol.

6. A process as claimed in claim 1 wherein R is monochlorophenyl, Z ismethyl and n is 1.

7. A process as claimed in claim 1 wherein R is dichlorophenyl and n is1.

8. A process as claimed in claim 1 wherein the compound of Formula I isin admixture with benzyl alcohol.

9. A process as claimed in claim 1 wherein the amount of compound havingthe Formula I or the mixture thereof with benzyl alcohol is within therange of from 0.25% to 5% by volume based on the total volume of the dyeliquor.

10. A process as claimed in claim 9 wherein the amount of the compoundhaving the Formula -I or the mixture thereof with benzyl alcohol iswithin the range of from 1% to 3% by volume based on the total volume ofthe dye liquor.

11. A process as claimed in claim 1 wherein the temperature at whichdyeing is carried out is from to C.

12. A process as claimed in claim 1 wherein the dyestuff is a cationicdyestuff containing onium groupings.

(References on following page) 15 16 References Cited OTHER REFERENCESUNITED STATES PATENTS H. F. Mark, Textile Chemist and Colorist, January3,506,990 4/1970 Richardson et a1. ms-17s R 1972, 4, P 3,056,644 10/1962 Radley et 5 GEORGE LESMES, primary Examiner 3313590 4/1967 De lanoet 8*173 T. J. HERBERT, JR., Assistant Examiner 3,402,986 9/1968 Zv1aket a1. 893 X 3,349,062 10/1967 Hill et a1 -8--178 R X U.S. Cl. X.R.

3,558,267 1/1971 Langenfield 12-17:; R X 893, 178

